A recent study published in Nature Ecology and Evolution has challenged a long-held assumption in biology that larger animals have proportionally larger brains. The research reveals that the relationship between brain size and body size is not as straightforward as previously thought.
For over a century, scientists have assumed that there is a linear relationship between an animal’s brain size and its body size. However, new research suggests that this assumption is not accurate. In fact, the study found that larger animals do not necessarily have proportionally larger brains, with humans being a significant exception to this rule.
The researchers gathered data on brain and body sizes from over 1,500 species of mammals and used advanced statistical models to analyze the relationship between the two. They discovered that the relationship is actually a curve, meaning that as animals become larger, their brains do not increase in size as quickly as their bodies do.
This finding was consistent across all the mammals studied, with some notable exceptions. For example, humans have evolved much faster than other mammals, resulting in large brain sizes today. The study also found that bats, which are among the smaller mammals, have undergone rapid changes in brain size early in their evolution but have remained relatively stable since then.
The researchers identified a “curious ceiling” in brain size, where there seems to be a limit preventing brains from getting too large in the largest animals. This pattern was also observed in birds, suggesting that it may be a general phenomenon across different biological makeups.
Overall, the study’s findings help resolve the controversy surrounding the relationship between brain and body size, providing new insights into animal intelligence, social behavior, and evolution.
Source: https://www.psypost.org/humans-are-the-exception-new-research-reveals-surprising-brain-size-trends-across-mammals/